The invention concerns a device for the alignment of tube segments
In the case of a known device of this type, the individual tube segments are laid on first conveyor belts that run mutually parallel. Running in addition to the first conveyor belts are second conveyor belts, equipped with stops and configured as cog belts. The second conveyor belts run at a slower speed than the first conveyor belts. Due to the difference in speed, the tube segments are moved until they come to lie against the stops of the second conveyor belts and are held in this contact position. Viewed in the direction of projection relative to the plane of conveyance, all conveyor belts extend at an angle relative to the direction of travel. The result of this is that the tube segments are pushed crosswise relative to the direction of travel up to their position on a limiting belt running laterally relative to the conveyor belts. To enable this position to be.
The known solution is suitable only for tube segments that are made sufficiently strong and rigid at their extremities. In the case of tube segments made from a few thin-walled or soft layers, a proper alignment is not possible using the known device, because they cannot withstand the pressure at the limiting belt and buckle. This danger is present in particular in the case of tube segments whose ends exhibit an angled cut. For such obliquely cut tube segments, the pressing forces must be absorbed by only one layer, independently of the number of remaining layers, namely, the furthest projecting outer layer.
A process and a device for conveying sheet layers from a collecting station of a machine for manufacturing flat material are furthermore already known from, for example DE 4,415,047 A1. This device serves to separate the stacked sheets arriving from a collecting station that have already been aligned as a stack. The known device does not encounter the problem of the alignment of tube segments, as occurs during the manufacture of sacks and bags. Other known publications which concern the conveyance and transport of individual elements likewise have no significant relevance to the problem addressed by the present invention: A device for the separation of tablets is known from DE 4,222,972 C2. A further known publication, DE 3,918,036 C2 discloses a device for grouping elongated parts transported in crosswise position, especially sectional bar stock. It does not anticipate aligned conveyance of already separated transport goods with little shape stability.
Moreover, a further publication DE 3,842,964 A1, discloses the formation of groups of articles, particularly for automatic packaging lines, which work with grippers.
U.S. Pat. No. 5,341,915 describes a conveyor system for a precise transport of articles such as food containers and includes a series of conveyor belts which all run in the direction of travel or parallel to one another.
Finally, yet another device is known (JP 6,283,920 A) which serves for the alignment and transport of fruit or the like. This publication discloses the inclined arrangement of conveyor belts or conveyor-belt zones. This known solution is unusable for the object of the present invention.
Starting from the state of the art described in the preamble to patent claim 1, the underlying object of the invention is to create a device of the type assumed to be known in such a way that it is also designed for the proper alignment of tube segments which do not exhibit flexural stiffness in all areas.
In the case of the design according to the present invention, transport takes place both in the direction of travel as well as for lateral alignment by means of entrainment means that grip the back wide side of the tube segments. The wide sides of the of the tube segments are in each case made sufficiently stiff in order to ensure orderly transport, both in the direction of travel as well as the crosswise direction. The entrainment means engaging the back wide side push the tube segments on the depository plane formed by the lower conveyor belts. The ends, which are sensitive to mechanical stress, of which only one is utilized for lateral alignment, are not subjected to any mechanical stress whatsoever in the case of invention. Rather, their position is scanned without making contact, and if the alignment position marked by the sensors is achieved, the reduction of the present the revolution rate of the conveyor belts carrying the entrainment means causes further transport in the aligned position to be assumed by conveyor belts then leading in the direction of travel. After correct alignment has taken place, the aligned tube segments are transferred to a further conveyor belt, with which it is assured that the alignment will no longer change.
A preferred embodiment(s) of the invention is/are described in detail below with the aid of the drawings. In the drawings: